Planned fixes and features

Better screenshots
Review how colors work in different terminals.
- Need to differentiate between dark and bright backgrounds.
- Accession color should be explicit
- Differentiate between coloring of sequences and "context" (accessions, indices, etc).
Add support for restricting to a sub-alignment.
Add option --glimpse.
Explicitly choose parts of an alignment to view/color.
Pypi.org does not handle MarkDown in the README. Should look for a solution.

Considered features

Automatic paging using (e.g.) less -R if alignment does not fit in one screen and env variable ALV_PAGER is set.
Coloring of motifs
Option -st, --sort-by-tree: Sort sequences based on a simply estimated tree, à la Belvu. Should be easy to implement using Dendropy.